1. Field of the Invention
The present invention relates to a quantum interference semiconductor device using an interference effect of electrons and to a method of making such a device and, more particularly, to a quantum interference semiconductor device which can also operate at a room temperature and to a method of making such a device.
2. Description of the Prior Art
In association with the progress of the recent ultrafine structure making technique, studies of a quantum interference device using the interference of electron waves are actively being performed. For instance, as a quantum interference transistor (hereinafter, referred to as an AB effect transistor) using an Aharonov-Bohm effect, a transistor using a double hetero junction of AlGaAs/GaAs as shown in FIG. 1 has been proposed (for example, refer to "Technical Digest of IEDM 86", pp. 76-79). In FIG. 1, reference numeral 101 denotes a GaAs layer; 102 an AlGaAs layer; 103 and 104 n.sup.+ contacts; and 105 an n.sup.+ type GaAs layer. In FIG. 1, a wave function of electrons is shown by a broken line.
On the other hand, in recent years, studies of the vacuum microelectronics grow prosperous. As a result of the studies, there is a micro vacuum tube using a semiconductor.
The AB effect transistor as shown in FIG. 1 or other quantum interference devices must be cooled to an ultralow temperature which is equal to or lower than a temperature (4.2 K) of liquid helium in order to hold coherency of electrons. Therefore, it is difficult to easily use them and they are disadvantageous from a viewpoint of costs.
On the other hand, in the conventional micro vacuum tube, the arrival of electrons which are generated from a cathode to an anode is controlled merely by changing a path of the electrons by a gate voltage which is applied to a gate and an interference effect of electrons is not used.